The national dock workers' federation in Greece has called for another 24-hour strike as protests against the government’s privatization plans continue.

The stoppage is being called for next Wednesday, January 30. The federation is also calling for its overtime ban run on throughout February.

Workers at Piraeus are also reported to have voted for their own 24-hour stoppage immediately following Wednesday's planned walkout.

According to a Lloyd's List report, haulage firms have held emergency talks with port management in an effort to secure a promise of a minimum number of daily container movements to keep vehicles and drivers active.

This fresh wave of strike action is said to be bringing Greek ports closer to a shutdown.

Reports say Piraeus, the country's largest port, could be shutdown in under two weeks.

Port authorities have warned that container storage terminals are already running close to capacity and that further strikes will exacerbate the congestion.

The strikes started this year after an announcement by Merchant Marine Minister George Voulgarakis that a global tender for operators to run Piraeus and Thessaloniki under a 30-year concession would be released.

The tenders are for management contracts for two of the three container facilities at Piraeus and for the entire container terminal in Thessaloniki.

Trade unions objected to the privatization and port workers have been protesting with 24-hour strikes and a ban on overtime.

There have also been clashes between strikers and police.

The privatization plans are still going ahead. Greek officials say the results of their global tenders to find private investors for Piraeus and Thessaloniki container operations should be available in early March.

The Thessaloniki Port Authority on January 15 approved the global tender process while the Piraeus Port Authority approved the tender conditions on January 11.

Reports say that up to 10 international parties have already asked for the tender documents for Piraeus.

According to Geroge Voulgarakis, the country's new shipping minister, the process does not constitute actual port privatization but rather the transfer of certain container operations to the private sector.

“The aim is to make the two ports competitive hubs that can be transshipment points for the wider region,” said Voulgarakis.

“Port workers' rights are protected,” he added.

According to a Hellenic Shipping News report, parties interested in the privatization include DP World, COSCO Pacific Limited, Maersk (APM Terminals BV.), Hutchison Port Holdings (HPH), and Zim Integrated Shipping Services Ltd (ZIM).